2D seismoelectric log simulation using a finite‐difference method

Abstract

Summary A finite-difference (FD) algorithm is presented for simulation of the 2D electr ic field induced by a point acoustic source in a fluid-filled borehole surrounded by porous media because of electrokinetic effects. Under the assumption that the reverse influence of the electric field on the acoustic field is negligible, we first use the velocitystress finite-difference time-domain method to simulate the acoustic field governed by Biot’s poroelastic wave equations (Biot, 1962). We then finite-difference simulate the induced electric field resulting from the grain/fluid displacements by applying Pride’s electrokinetic coupling theory (Pride, 1994). The FD algorithm is validated by comparisons against the analytical real-axis integration method. The seismoelectric logs in heterogeneous porous formations with a horizontal interface are simulated with the FD algorithm.